Venipuncture Sites and Specimen Collection

• Venipuncture should use a site that provides the best blood return.

Resources for Venipuncture

• 70% Isopropyl Alcohol
• Tourniquet
• Wet and dry cotton
• Gloves

Venipuncture Defined

• Securing intravenous access for intravenous therapy or venous blood sampling.
• Healthcare professionals who perform this procedure include Medical Laboratory Scientists, Medical Practitioners, Phlebotomists, and Nursing Staff.

Accurate Specimen Collection

• Following a standard procedure when collecting blood samples is essential for accurate lab results.
• Errors in collection or test tube labeling can lead to incorrect results.

Primary Vein Choice

• The median cubital vein is the primary vein used, located in the middle arm.
• Other suitable veins in the upper arm include Basilic, Cephalic, or Median veins.

Sites to Avoid for Venipuncture

• Areas with extensive scarring from burns or surgery
• Edematous arms
• Upper extremities where a mastectomy has been performed
• Any hematoma, regardless of its size; if unavoidable, perform venipuncture distal and below the hematoma
• Areas with intravenous therapy or blood transfusions; if unavoidable on the opposite arm, draw blood below and distal to the IV after turning off the IV infusion for at least 2 minutes before performing venipuncture.
• Sites with cannulas or fistulas
• Arms in casts
• Sites with birthmarks, moles, and tattoos
• Apply the tourniquet between the IV site and the venipuncture site.

Venipuncture Procedure

• Wear appropriate PPE.
• Prepare the equipment.
• Select the best puncture site.
• Position the patient’s arm slightly bent in a downward position.
• Apply the tourniquet 3 to 4 inches above the selected puncture site.
• Avoid applying the tourniquet too close to the puncture site, as it may cause the vein to collapse.
• Make sure the free end of the tourniquet is away from the puncture area, without any folds.
• Leave the tourniquet on for no more than 1 minute to prevent hemoconcentration and hemolysis.
• Ask the patient to make a fist to make the vein more palpable, but avoid "pumping" the fist.
• Palpate the vein using the index or middle fingers in vertical and horizontal directions to assess its depth, direction, and size.
• Release the tourniquet and ask the patient to open their fist, unless you can locate, palpate, and extract within a minute.
• Sanitize the area with 70% alcohol in a circular motion from the center outwards allowing the area to air dry.
• Do not blow or fan on the venipuncture site.

Important Considerations

• Median Cubital and Cephalic veins are the most common choice for venipuncture.
• Alternative placement choices are the basilic vein on the dorsum of the arm or dorsal hand veins.
• Use the basilic vein, only if no other prominent arm vein is available due to its proximity to the brachial artery and median nerve.
• Reserve veins in the foot and ankle as a last resort.
• Avoid veins on the underside of the wrist.

Venipuncture involves securing IV access or sampling venous blood, typically performed by healthcare professionals. The median cubital vein is the primary choice, but others may be suitable. Avoid areas with scarring, edema, or upper extremities affected by mastectomy to ensure accurate specimen collection.